Injector overflow mechanism



Oct. 4, 1938.

Bl E. FOLKE vINJECTOR OVERFLOW MECHANISM Filed May 2, 1938 s Sheets-Sheet 2 FIG 2 BEA/67' E. FOL/ 5 INVENTOR ATTORNEY FIG. 5

INJECTOR OVERFLOW MECHANISM Filed May 2, 1958 3 Sheets-Sheet 3 ATTORNEY Patented Oct. 4, 1938 UNITED v STATES rA'reargorri ce1,."

INJECTOR ovERFLow MECHANISM Bengt E, Folke, Mamaroneck, N. Y., assignorto Nathan Manufacturing Company, New York, ,-N. Y., a corporation of New York Application May 2, 1938, Serial No. 205,499

19- Glaims.

Injectors of the open overflow type have, as is well-known in the art, one or more relief ports inthe combining njozzles, opening into the over flow chamber which is closed against the admission of air by a check valve. This overflow valve is under normal conditions held against itsseat by its own ,weight so that the slight pres sure' of the waterflowing into the injector will raise the, check valve from its seat and overflowinto a passage provided for this purpose.

When starting an injector, water entering the instrument must have a ready outlet to permit the surplus waterto escape until the combined steam and water attains sufficient velocity to enter the boiler, as otherwise a back pressure would be produced which wouldjdisrupt the continuity of the jet and prevent theprompt starting of the injector. This disruption of the jet termed breaking of the injector may occur in starting the injector, orafter the injector is in operation if for any reason the water supply should be temporarily interrupted. This may take place, for example, on a locomotive traveling. at a high rate of speed, when thewater rolls considerably with a low levelin the tank. Modern injectors are usually so constructed that when the, water supply is restored'the injector will automatically restart of its own accord, so long as the water is free to pass out through ,the overflow. 7i; Under normal operation of the injector a partialvacuum exists in the chamber surrounding the combining nozzles, this chamber being closed by the above-mentioned overflow valve. When,

at the overflow. All such arrangements, however, as known to me, have the common'drawback that they do not permit dependable restartingof the injector should .the' instrument break. due to surging of water in the tank, with- 50? out shutting off the injector entirely and starting it again by opening first the water valve and then'the steam valve in the manner wellknown in the art.

'It-is: the principalobject of this invention to provfdemeansin an injector to: close the overflow automatically assoon as the injectorfhas started and tdope'n" the overflow automatically when the water supply of the injector should be momentarily interrupteds if Another object is to provide a mechanism which fi is simple and dependable in its operation and suitable for 'a' wide range 'offoperating requirements.

Further objects will become apparentfin the specification and the accompanying drawings; in l'i i which a preferred embodiment of the invention is shown.

In the drawings, I n V r Fig. I shows an injector embodying the principles of the invention, partly in elevationand 1W partly in section? A n Fig; 2 is a plan "view of the injector partly in section along the line 2-2 in Fig. 1;

Fig. 3 shows a sectional view partly in elevation substantially along theline 3+3 in Fig. 2 showing the "overflow valve and theactuating overflow mechanism in the positionlwhic'h they assume whentheinjector is not working? J Q Fig. 4 shows the actuating mechanism "for 'the overflow valve in the position which it a sum when the injector isoperating; n H Fig. 5 showsthe overflow valve in its closed position whilethe injectoris operating;

Fig. 6 is a modified form of overflow actuating mechanism and Fig. 7 is an endviewof the drain valve proper of the overflow actuating mechanism shown in Fig.6

Like characters of reference denote similar parts throughout the several views and through- 5 out the following specification.

Referring particularly to Fig. 1, llliis an in: jector providedwith asteam inlet at] H and water inlet at |2,,',steam-nozzles l3 and l' l c'ondensing nozzles l5, l5 and Ill and ,del'iverynozzle it. A delivery check valve i9 is located in the discharge line 20. Overflow openingstl communicate with overflow chamber 22 closed by overflow check valve 23, which, when open, permits water to be discharged through the waste passage 24 and the overflow pipe 25. All' parts just described are common to the conventional form of an injector] e A steam pipe 26 connects the injector steam inlet H with an overflow control valve 21', A"

pipe 28 connects the overflow control valve 2T with an overflow operating cylinder 29. The overflow control valve 21 is provided witha relief'pipe 30 shown in Fig z and more clearly 11-" lustra'ted in Fig.3. r

A steam valve (not shown) actuated by an operating lever is connected to the steam inlet H and serves to open and close the steam supply to the injector. 33 is the stem of a valve used to open and close the injector water inlet.

Referring now particularly to Fig. 3, control valve casing 21 is attached by means of a screwed connection 34 and adapter 35 to the injector delivery chamber 36. Piston valve 31 is loosely fitted in the bore 38 of the control valve casing 21. The bottom of the piston 31- is provided with a stop 31a which contacts extension 39 when piston 31 isin its bottom position as shown in Fig. 3. The upper part of piston 31 is provided with a seat 40 which forms a tight joint with shoulder 4| at the upper end of the bore 38 in control valve casing 21 when the piston 31 is in its uppermost position as shown in Fig. 4. A ball check valve 42 is permitted to seat against seat 43 when piston 31 is in its top position. A shoulder 44 serves to push the ball valve 42 off its seat 43 when the piston 31 moves downwardly from its top position. Seat 43 is provided for at the inner end of a nipple 43a which has a relief port 43b through its center to which is coupled relief pipe 30 opening preferably into the atmosphere.

In Fig. 6 is shown a modification of the overflow control valve 21 in which in place of the ball check 42 a flat-seated valve 42a provided with notches 42b at its periphery, as shown in Fig. 7, and with a stem 420 is used. The stem 420 contacts with the shoulder 44 when the piston 31 is in its downward position, causing the valve to be tilted slightly and open a relief port 42d in a nipple 426 which connects by means of a coupling to the exhaust pipe 39. When the piston is in its uppermost position a coil spring 42 forces the flat seat of the valve 42a to close the port 42d.-

An overflow operating piston 45 is fitted within a sleeve 46 in overflow operating cylinder 29, and is normally held in its upper position by a coil spring 41 acting against a shoulder 48 of the piston 45, as clearly shown in Fig. 3. Inside of the piston 45 and at its bottom end is located a compressed coil spring 49 holding a cup-shaped follower 56 against a screwed-in ring 5i. When in its lower position, piston 45 makes a tight seal with seat 52 located at the lower end of sleeve 49, as is clearly shown in Fig. 5. Overflow check valve 23 is provided with a stem 53 which is free to slide in a guide 54. Casing 29, sleeve 46 and guide 54 are attached to the injector body 10 by means of a coupling nut 55. 7

The upper part of the casing 29 is provided with a coupling connection 56 connecting the pipe 28 to a similar connection 51 at the side of overflow control valve casing 21 and communicates with the interior of the casing 21 by inlet port 58.

A threaded spindle 59 is provided for the purpose of manually closing the overflow, for example, when the injector is being heated with steam to prevent freezing or when forcing steam into the tender of a locomotive through the injector to heat the water supply.

The operation of the injector is as follows:

When the injector is started steam flows through inlet H and connecting pipe 28 into the 'control valve body 21 and builds up a pressure on top of control valve piston 31, holding the piston in the bottom position with stop 31a in contact with extension 39. The space on top of operating piston 45 in the overflow operating cylinder 29 is relieved of pressure through pipe .28, inlet port 58 and relief opening 43b, opento communicated to the under-side of piston 31 through the openings 60 in the adapter 35. After the injector has been started, the delivery pressure acting on the under-side of piston 3'! will exceed the steam pressure acting on top of the piston and will lift the piston into its top position as shown in Fig. 4 until the seat 49 contacts shoulder 4|. During this upward movement, leakage of steam and water around the loosely fitted piston 31 will carry the ball check 42 against its seat 43. When in its top position, a lower edge 6| of the piston 31 will have uncovered inlet port 58, thereby opening communication from delivery chamber 36, passages 69, inlet port 58 and pipe 28 to the top of the overflow operating piston 45 in the operating casing 29. Pressure built up on the piston 45 will overcome the resistance of spring 41 and force the piston 45 downwardly, carrying with it the compressed spring 49 and the cup-shaped follower 59. The follower 59 will contact the top of overflow check valve stem 53 at 62 shortly before piston 45 has reached its extreme bottom position, causing the spring 49 to exert its full pressure through the follower 59 on top of the valve stem 53 at the time when piston 45 reaches its bottom position and rests against seat 52. This position is clearly shown in Fig. 5. Attention is particularly drawn to the fact that the load on the overflow valve 23 is controlled by the compression of spring 49 and is independent of the amount of the delivery pressure on top of the piston 45 communicated from the delivery chamber through pipe 28.

If the operation of the injector should be temporarily disturbed, for example, by the interruption of the water supply, the pressure in the delivery chamber 36 acting on the lower part of piston 31 will become less than the steam pressure on top of piston 3'l causing this piston to be forced down and its shoulder 44 to engage ball check 42, forcing it off its seat 43. When piston 3! reaches its bottom position, inlet opening 58 will then be in direct communication with relief port 43b causing immediate release of the pressure on top of piston 45 through pipe 28 and permitting coil spring 41 to exert its pressure against shoulder 48 of the piston 45 and bring it back into its top position, as shown in Fig. 3. The overflow check valve 23 will then be free to lift from its seat and will place the injector in a position ready to start as soon as the temporary interruption of water has been overcome.

As soon as the injector has restarted, the action of the pressure in the delivery chamber 36 on piston 31 will again cause the overflow operating piston 45 to move downwardly and enable the spring 49 and cup-shaped follower 50 to exert pressure on the overflow check valve 23 holding it against its seat, thereby preventing a spill at the overflow.

It is obvious that while I have disclosed the overflow mechanism in connection with a horizontal type of injector and detachable to its bodyproper, the same may be applied to vertical types of injectors as well, and moreover, instead of being detachable, as shown, may be made part of the injector body, if so desired.

It is understood that various other changes of form, proportions and minor details of construc- BOI- tionymay be resortedtowithout-departing from the principles or sacrificing any of the advan tages of the invention astdefined in the appended claims. 1 1 l .What I claim as newis: r 1.: Actuating mechanism for the overflow valve of, an injector comprising a housing and a piston therein, the. said housing having a steam inlet connected to the steam supply of the injector, a duct tothe overflow valve, a passage to the delivery chamber of the injector and'an outlet to theatmosphere, the said piston being operated by steam pressure from the saidinlet at one end i and by fluid pressure from the said delivery chainher at the other end, and separate valve means adapted to be" actuated by the piston to'jopen communication between the duct to the overflow valve and the outlet to the atmosphere when the said steam pressure exceeds the said fluid pressure, the same valve means being adaptedto close communication between the said duct and the atmosphere when the flu d pressure exceeds the steam pressure.

- 2. Actuating mechanism" for the overflow valve of an injector comprising a'hous'ing and a piston therein, thesaid' housing having a steam inlet 7 connected to'the steam supply of theinjectoga duct to the overflow valve, a passage to the delivery chamber of the injector and an outlet to the atmosphere, fitted ends on the saidpiston and a reduced center portion between them defining a passage chamber, the said piston being actuated .by'steam pressure from the said inlet at one end and by fluidpressure from the said delivery chamber at the other end, and separate valve means adapted to be actuated by the piston to open communication between the duct from the overflowlvalve and the outlet to the atmosphere through the said passage chamber when the said steam pressure exceeds the said fluid pressure, the same valve means being adapted to close communication between the duct and the atmosphere when the fluid pressure exceeds'the steam pressure.

3.. Actuating mechanism for the overflow valve of an injector comprising a housing and a piston therein, the said housing having a steam'inlet connected to the steam supply of the injector, a

duct to the overflow valve, a passage to the delivery chamber of the injector, and a separate check controlling an outlet to the atmosphere,

the said check being held open by the said piston whenithe injector is inoperative, the saidpiston adaptedlto be moved by fluid pressure in the delivery chamber to close the said steam inlet and piston within'the housing having a reduced center portion and loosely fitted upper and lowerends, its upper end being adapted to close thesaid steam inlet and its lower end being below the saidduct when the injector is inoperative, and a separate check controlling an outlet to meat mosphere, the said outlet being disposed between the said upper and lower ends and its check being held open positively by the said piston when the injector in inoperative.

5. In an actuating mechanism for the overflow valve of an injector, a housing having a steam linlet, a duct to the overflow valve, a passage to the delivery chamber of the injector and an; outlet to the atmosphere, a piston within the housing adapted to be operated by steam pressure from the said inlet at one end and by-fluid' pressure from the said. delivery chamber atthe' inlet, a duct to the overflow valve and a passage to the delivery chamber of the injector, a piston within the housing having fitted ends. and av reduced center portion between them defining a passage chamber having an outlet to the atmosphere through the housing, the said piston being actuated by steam pressure from the said inlet at one vend and by fluid pressure from the said delivery chamber at the other end, andvalve means separate from the said piston adapted to. close the said outlet when the said fluid pressure exceeds the said steam pressure, the said piston opening the said valve means when the steam pressure exceeds the fluid pressure. '7. In an overflow'closing device for an injecto a casing having a fluid prssure connection to the delivery chamberof the injector, an overflow valve, a piston adapted to beiorced to a seat and permit the overflow valve to open after the fluid pressure in the casing has been exhausted to the atmosphere.

8. In an overflow closing device for an injector, a casing having a fluid pressure connection to the delivery chamber of the injector, an overflow valve, 2. piston adapted to be forced to a seat with in the casing by fluid pressure from the said connection, a stop separate from and'yieldingly disposed within the said piston to close the said overflow valve when the piston contactswith its seat, a spring independent of the saidstop to force the said piston away from. its seat and permit the' overflow valve to open after the fluid pressure in the casing hasbeen exhausted to the atmosphere, and optional manual means in the said casing to close the said overflow valve.

9. In an overflow closing device for an injector, a casing having a fluid pressure connection to the delivery chamber of the injector, an overflow valve, a sleeve within the casing having a seat at its bottom, a piston adapted to be forced to the said seat by fluid pressure from the said connection, a stop separate from and yieldingly disposed within the said piston to close the said overflow valve when the piston contacts with its seat, and a spring independent of the said stop to force the said piston away from its seat and permit the overflow valve to open after the fluid pressure in the casing has been exhausted to the atmosphere.

1!). In an overflow closing device for an injector,

a casing having a fluid pressure connection to the delivery chamber of the injector, an overflow valve, 'a guide for the overflow valve, a sleeve within the casing having a seat at its bottom, a

nut adapted to couple the said guide, casing and sleeve to the injector, a piston adapted to be forced to the said seat by fluid pressure from the said connection, a stop separate from and yieldingly disposed within the said piston to close the said overflow valve when the piston'contacts with its seat, and a spring independent of the said stop to force the said piston away from its seat and permit the overflow valve .to open after the fluid pressure in the casing has been exhausted to the atmosphere.

ll. In an overflow closing device for an injector, a casing having a fluid pressure connection to the delivery chamber of the injector, an overflow valve, aguide for the overflow valve, a-sleeve within the casing having a seat at its bottom, a nut adapted to couple the said guide, casing and sleeve to the injector, a piston adapted to be forced to the said seat by fluid pressure from the said connection, a stop separate from and yieldingly disposed within the said piston to close the said overflow valve when the piston contacts with its seat, a spring independent of the said stop to force the said piston away from its seat and permit the overflow valve to open after the fluid pressure in the casing has been exhausted to the atmosphere, and optional manual'means in the said casing to close the said overflow valve.

12. In an injector, an overflow valve, a casing for the valve, an actuating mechanism comprising a housing and a piston therein, the said housing having a steam inlet connected to the steam supply of the injector, a duct to the said casing, a passage to the delivery chamber of the injector and an outlet to the atmosphere, the said piston being operated by steam pressure from the said inlet at one end and by fluid pressure from the said delivery chamber at the other end, and separate valve means adapted to be actuated by the piston to open communication between the duct to the casing and the outlet to the atmosphere when the said steam pressure exceeds the said fluid pressure, the same valve means being adapted to close communication between the said duct and the atmosphere when the fluid pressure exceeds the steam pressure, the said casing for the overflow valve having a closing piston adapted to be forced to a seat within the casing by fluid pressure from the delivery chamber through the said duct, a stop separate from and yieldingly disposed within the said closing piston to close the overflow valve when the piston contacts with its seat in the casing, anda spring to force the closing piston away from its seat and permit the overflow valve to open after the fluid pressure in the casing has been exhausted to the atmosphere through the outlet in the said housing.

13. In an injector, an overflow valve, a casing for the valve, an actuating mechanism comprising a housing and a piston therein, the said housing having a steam inlet connected to the steam supply of the injector, a duct to the said casing, a passage to the delivery chamber of the injector, and an outlet to the atmosphere, the said piston having fitted ends and a reduced center portion between them defining a passage chamber and being operated by steam pressure from the said inlet at one end and by fluid pressure from the said delivery chamber at the other end, and separate valve means adapted to be actuated by the piston to open communication between the duct to the casing and the outlet to the atmosphere through the said passage chamber when the said steam pressure exceeds the said fluid pressure, the 'same valve means being adapted to close communication between the said duct and the atmosphere when the fluid pressure exceeds the steam pressure, the said casing for the overflow valve having a closing piston adapted to be forced to a seat within the casing by fluid pressure from the delivery chamber through the said duct, a stop separate from and yieldingly disposed within the said closing piston to close the overflow valve when the piston contacts with its seat in the casing, and a spring to force the closing piston away from its seat and permit the overflow valve to open after the fluid pressure in the casing has been exhausted to the atmosphere through the outlet in the said housing.

14. In an injector, an overflow valve, a casing for the valve, an actuating mechanism comprising a housing and a piston therein,the said housing having a steam inlet connected to the steam supply of the injector, a duct to the said casing, a passage to the delivery chamber of the injector and an outlet to the atmosphere, the said piston being operated by steam pressure from the said inlet at one end and by fluid pressure from the said delivery chamber at the other end, and a separate valve for the outlet to the atmosphere adapted to close when the said fluid pressure exceeds the said steam pressure and adapted to be opened by the said piston when the steam pressure exceeds the fluid pressure to open communication between the duct to the casing and the said outlet, the said casing for the overflow valve having a closing piston adapted to be forced to a seat within the casing by fluid pressure from the delivery chamber through the said duct, a stop separate from and yieldingly disposed within the said closing piston to close the overflow valve when the piston contacts with its seat in the casing, and a spring to force the closing piston away from its seat and permit the overflow valve to open after the fluid pressure in the casing has been exhausted to the atmosphere through the outlet in the said housing.

15. In an injector, an overflow valve, a casing for the valve, an actuating mechanism comprising a housing and a piston therein, the said housing having a steam inlet connected to the steam supply of the injector, a duct to the said'casing and a passage to the delivery chamber of the injector, the said piston having fitted ends and a reduced center portion between them defining a passage chamber having an outlet to the atmosphere through the housing and being actuated by steam pressure from the said inlet at one end and by fluid pressure from the said delivery chamber at the other end, and separate valve means adapted to be actuated by the piston to open com munication between the duct to the casing and the outlet to the atmosphere through the said passage chamber when the said steam pressure exceeds the said 'fluid pressure, the same valve means being adapted to close communication between the' said duct and the atmosphere when the fluid pressure exceeds the steam pressure, the said casing for the overflow valve having a closing piston adapted to be forced to a seat within the casing by fluid pressure from the delivery chamber through the said duct, a stop separate from and yieldingly disposed within the said closing piston to close the overflow valve when the piston contacts with its seat in the casing, a spring to force the closing piston away from its seat and permit the overflow valve to open after the fluid pressure in the casing has been exhausted to the atmosphere through the outlet in the said housing, and optional manual means in the said casing to close the said overflow valve.

16. In an injector, an overflow valve, a casing for the valve, an actuating mechanism comprising a housing and a piston therein, the said housing having a steam inlet connected to the steam supply of the injector, a duct'to the said casing, a passage to the delivery chamber of the injector and an outlet to the atmosphere, the said piston being operated by steam pressure from the said inlet at one end andby fluid pressure from the said delivery chamber at the other end, and separate valve means adapted to be actuated by the pressure from the delivery chamber through the said duct, a stop separate from and yieldingly disposed within the said closing piston to close the overflow valve when the piston contacts with its seat in the casing, a spring to force the closing piston away from its'seat and permit the overflow valve to open after the fluid pressure in the cas ing has been exhausted to the atmosphere through the outlet in the said housing, and optional manual means in the said casing to close the overflow valve.

17. In an injector, .an overflow valve, a casing for the valve, an actuating mechanism comprising a housing and a piston therein, the said housing having a steam inlet connected to the steam supply of the injector, a duct to the said casing, a passage to the delivery chamber of the injector and an outlet to the atmosphere, the said piston being operated by steam pressure from the.

said inlet at one end and by fluid pressure from the said delivery chamber atthe other end, and separate valve means adapted to be actuated by the piston to open communication between the duct to the casing and the outlet to the atmosphere when the said steam pressure exceeds the said fluid pressure, the same valve means being adapted to close communication between the said duct and the atmosphere when the fluid pressure exceeds the steam. pressure, the said casing for the overflow valve having a sleeve with a seat at its bottom, a closing piston adapted to be forced to the said seat by fluid pressure from the delivery chamber through the said duct, a stop separate from and yieldingly disposed within the said closing piston to close the overflow valve when the piston contacts with its seat in the sleeve, and a spring to force the closing piston away from its seat and permit the overflow valve to open after the fluid pressure in the casing has been exhausted to the atmosphere through the outlet in the said housing. 1

18. In an injector, an overflow valve, a casing for the valve, an actuating mechanism comprissupply of the injector, a duct to the said casing, a passage to the delivery chamber of the injector and an outlet tothe atmosphere, the said piston being operated by steam pressure from the said inlet at one end and by fluid pressure from the said delivery chamber at the other end, and separate valve means adapted to be actuated by the piston to open communication between the duct to the casing and the outlet to the amosphere when the said steam pressure exceeds the said fluid pressure, the same valve means being adapted to close communication between the said duct and the atmosphere when the fluid pressure exceeds the steam pressure, the said casing for the overflow valve having a sleeve with a seat at its bottom, a guide for the overflow valve, a closing piston adapted to beforced to the said seat by fluid pressure from the delivery chamber through the said duct, a nut adapted to couple the said guide, casing and sleeve to the injector, a stop separate from and yieldingly disposed within the said closing piston to close the overflow valve when the piston contacts with its seat in the sleeve, and a spring to force the closing piston away from its seat and permit the overflow valve to open after the fluid pressure in the casing has been exhausted to the atmosphere through the outlet in the said housing.

19. In an injector, an overflow Valve, a casing for the valve, an actuating mechanism comprising a housing and a piston therein, the said housing having a steam inlet connected to the steam supply of the injector, a duct to the said casing, a passage to the delivery chamber of the injector and an outlet to the atmosphere, the said piston being operated by steam pressure from the said inlet at one end and by fluid pressure from the said delivery chamber at the other end, and separate valve means adapted to be actuated by the piston to open communication between the duct to the casing and the outlet to the atmosphere when the said steam pressure exceeds the said fluid pressure, the same valve means being adapted to close communication between the said duct and the atmosphere when the fluid pressure exceeds the steam pressure, the said casing for the overflow valve having a sleeve with a seat at its bottom, a guide for the overflow valve, a closing piston adapted to be forced to the said seat by fluid pressure from the delivery chamber through the said duct, a nut adapted to couple the said guide, casing and sleeve to the injector, a stop separate from and yieldingly disposed within the said closing piston to close the overflow valve when the piston contacts with its seat in the sleeve, a spring to force the closing piston away from its seat and permit the overflow valve to open after the fluid pressure in the casing has been exhausted to the atmosphere through the outlet in the said housing, and optional manual means in the said casing to close the said overflow valve.

BENGT E. FOLKE. 

